Manufacture of benzanthrone derivatives



PatentedDec. s,-1 9z5.

UNITED 'ST'HATQESJ'. PATEN "OFFICE.

ARTHUR nnrrnmenaus AND nnco' won-r, or mmmnm. am) nnmnrcn:

nnnnsnnmnn, o3 LonwmsnArmI-oN-rnn-nnmn, GERMANY, assrenons 'ro' BADISCHE ANILIN- a SODA-FABBIK, or nunwlcsnu'nu-oN-rnE-nnmn, can.-

MANY, A CORPORATION OF msuorac'run'n or imnzmrnnonn nnnrvi'nvns.

No Drawing.

To all whom it may concern? Be it knownthat we, ARTHUR Lorraine- HAUS, HUGO WoLFF, and HEINRICH NERE- sHEIMER, citizens the first two of the German Empire, the third of the Kingdom of the Netherlands, residing the first two at Mannheim, the third at Ludwigshafen-on-the- Rhine, Germany, have invented new and useful Improvements in the Manufacture of Benzanthrone Derivatives, of wlfich the following is a specification.

As is known benzanthrone and its derivativescan be converted intovaluable dye stufis by melting with caustic alkalies in the presence or absence. of solvents ordiluting media.

Dhe present invention relates to the production, by alkalinecondensation, of certain intermediate products and to the production of coloring matters with their aid.

We have discovered that benzanthrone or its derivatives can be transformed by the ac'tlon of alkaline condensing agents, into Application filed April 26,1923. Serial No. 684,848.

ma 'be regarded as 2.2'-dibenzanthronyls,

hit er'to unknown of the following type:

condensation products which are not vat dyestufis but which are very valuable interme'di ate products for the production of coloring matters. For obtaining the new condensation products the alkaline condensing agents are applied under more moderate conditions than are required for the formation of the known coloring -matters from the benzanthrone compounds. Such conditions may consist in a lower temperature, short ervtimeof treatment, less concentrated condensing agents and so on, of which the lower temperature is the most important varlgttion;

- however, the'exact conditions depend on the circumstances in each "case, the diluent or condensing means employed and the like and can be ascertained in each single case without difficulty.

As to the nature of the new compounds thus obtained it may be stated that it. may

be assumed from the results of analysis and the reactions of the compounds that they valuable in view of their eing readily conproducts are very verted into vat coloring matters. The

known dibenzanthrone dyestufis are obtained by subjecting them to condensation I inmany various. ways. It can be done in some cases by simpl heating the intermedi ate products, or con ensing agents of an acid or alkaline nature or of weakly. oxidizing property can be employed; When condensing agents are a plied that have also a halogenatmg or sul onating action such as the free halogens or sulfuric acid, halogen or sulfonic acid derivatives of the dibenzanthrone may formed. Products of a dif-. ferent nature are produced with good yields,

when the c densation is effected by means of strong oxidizing agents, oxygen beilrlilg thenintroduced into the molecule S1111 However, we do not wish to bind ourselves t aneously, and oxidized dibenzanthrone without departing from the scope of the said invention. I The parts are "by weight. E wa'mp-Ze 1.

Introduce parts of benzanthrone into a melt consisting of 500 parts of potassium hydroxid and 300 parts of ethyl alcohol the temperature not surpassing 100 degrees centigrade and stir continuously for some hours at from 95 degrees to 100 degrees centigrade. Then boil the melt with water, remove the solution by filtering and purifying the resi due which is a dark powder, with a suitable solvent, for example acetone, to remove easily soluble by-products. A greenish-yellow productwill be obtained. which by crystallization from solutions of a high boiling point, preferably with the addition of animal charcoal, can be obtained in the form of small yellow needles melting above 300 degrees centigrade. l hey are difiicultly soluble in glacial acetic acid, benzene, or acetone, and easily soluble in high boiling solvents such as nitrobenzene or trichlorbenzene, the solutions having a yellow color.- In concentrated sulfuric acid the product dissolves with an intensely red color.

When condensation is performed at somewhat higher temperatures the final product may contain more or less dibenzanthrone, the knownblue violet vat dyestufi', which may be removed by treating the product with an alkaline hydrosulfite solution.

Ethyl alcohol may be replaced by other alcohols, the temperature being suitably varied according to the special circumstances. In the case of methyl alcohol, for

' instance, somewhat higher temperatures are suitable, for example from 110 degrees to 115 degrees centigrade.

Ear-ample 2. a

50 parts of benzanthrone are boiled under a reflux cooler with parts of potassium sulfitesolution in order to remove the vat.

dyestutf which may have been formed simultaneously. Theproduct may then be purified, if it should be found necessary, as described in the foregoing first example.

Example 3.

180 parts of benzanthrone are introduced at about 30 degrees centigrade into a solution of 240 parts of sodlum anilide (prepared from 58 parts of metallic sodium) in 800 .parts of anhydrous aniline in a current of nitrogen, whereupon the liquid is heated to 45 degrees centigrade for from 2 to 3 hours. The cherry-red solution is poured into dilute hydrochloric acid, whereby the reaction product is precipitated inythe form of brownish red flakes which are filtered off; washed and dried. They can be further purified as described in Example 1, the final product thus obtained being identical with the product there described.

Emample 4.

8.5 parts of sodium amid are introduced into 200 parts of mono-methyl-aniline in a current of nitrogen; the mixture is heated to about 180 degrees centigrade until ammonia is no longer generated. Then cool to about 75 degrees centigrade and add 20 parts of benzanthrone. After the temperature has been kept at from 75 degrees to degrees centigrade for 2 hours, the reaction product is dissolved in dilute hydrochloric acid. The brownish-red body precipitated thereby is filtered off, washed and dried. The impurities contained therein may be extracted with boiling alcohol. The insoluble part which may be subjected to further purification, is identical with the com oundobta-ined according to the foregoing Example 1.

In. an analogous'manner other condensing agents or diluents and derivatives of benzanthrone may be employed, the temperature being chosen in each case low enough to avoid the substantial formation of vat dyestuff. The conditions Vary to some degree according to the circumstances of the case. For example, G-methylbenzanthrone, when employed instead of benzanthrone. in Example 1 will give a compound very similar to that obtained from benza-nthrone itself;

its meltin oint is above 350 de rees centis P a:

grade.

. Ewa-mple 5.

10 parts ofthe intermediate product obtained according toeither of the aforesaid Examples 1 to 4 are mixed with 100 parts of 12.4.-tri-chlor-benzene, the mixture heated to from 1 10 degrees to 150 degrees centigrade and 25 parts of anhydrous aluminium chlorid are introduced at this temperature. The mixture is kept at this temperature while stirring until the formation of the dyestufi' is completed. vThe product is freed from tri-chlorbenzcne and aluminium chlorid in the usual way and is chemically identical with the known dihenzanthrone described for instance in the specification of Letters Patent No. 818,992.

E sample 6.

10 parts of the intermediate product described in the foregoing Examples .1 to 4 are heated for a short time with 300 parts of sulfuric acid of 82 per cent and l-part of mercuric sulfate to from 230 degrees to v240 nearly vents,

- chloric acid is entirely sol'ubld degrees centigrade. I The mass will thicken to a stiff paste. Pure dibenzanthrone can be obtainedtherefrom by filtering and washing first withsulfuric acid of 82 per cent and then with water.

Example '7.

l0 parts-of the condensation product obtained according to the foregoing Examples 1 to 4 are introduced at from 236 degrees to 240 degrees centigrade into 80 parts of fused potassium hydroxid and kept at this temperature for some hours while stirring. lVhen cool, the melt is boiled with water while passing air through until the dibenzanthrone which has been formed with a Quantitative yield is precipitated. It is then filtered off and washed. The potassium hydroxid can also be employed in the presence of alcoholsand' other organic sollene or others. Other alkaline condensing agents can also be employed.

Example 8.

parts of the-condensation product prepared accordlng to either of the foregoing Examples 1 to tare mixed with 150 parts i of anhydrous ferric' chlorid and 100 parts of dry common salt and heated to from 200 degrees to 210 degrees centigrade until a test portion after extraction with dilute hydroin an alkaline hydrosulfite solution.

The dyestutf produced contains chlorine;

its reddish-violet vat dyes cotton a somewhat dullbluish-violet shade.

i a Example v v VOl'k according to Example5 substituting for aluminium chlorid 30 parts of an-- hydrous ferric chlorid. A chlorinated dibenzanthrone is obtained, dyeingcotton from a blue vat more' bluish and purer "shades than dibenzanthrone.

It dissolves in high boiling solvents with a reddish-violetcolor and an intensely red fluorescence and in sulfuric acid with a violet color.

' Example 10.

temperature mixture is then heated to the boiling temor diluents, such as aniline, naphthain sulfuric acid with a" red color.

vat cotton is dyed brilliant violet shades of very good fastness. The solution in high boiling organic solvents shows a color simi lar to that'of the dyestuif described in the foregoing example. In concentrated sulfuric acid the dyestuif dissolves with a crimson red color. 4 I

E xamplc 11.

10 parts of metallic sodium are dissolved in 400 parts of anhydrous aniline, while heating in an atmosphere of nitrogen, then 30 parts of the condensation product prepared according to the foregoing Examples 1 to 4 are introduced into the solution thus formed of sodium anilide in aniline at a of 160 degrees centigrade. The

perature until the formation of the dyestulf no longer increases. When cold, the reddish-violet mass is poured into diluted hydrochloric acid, the precipitated coloring matter is filtered off, washed and dried. It M may be purified by boiling. with organic solvents. Metallic sodium may be replaced by other like metals, such as potassium, calcium, magnesium, aluminium and even other compounds of aromatic amines and like metals may be used such as sodium-monomethylanilide. Example'lz.

The condensation product obtained according to the Examples 1 to 4 is treated with fuming sulfuric acid containing about 10 10 percent of sulfuric .acid anhydrid at a low temperature. A sulfonic acid is formed representing a greenish-yellow powder, dissolving with a yellow color in water and V 10 parts of this sulfonic acid are heated for half an hour to from 200 degrees to 210 degrees centigrade with parts of sulfuric acid of 90 per cent and 1 part of mercuric sulfate. Dibenzan'throne sulfonic acid is formed 110 which separates from the mixture when still hot, it is filtered off when cool, washed with sulfuric acid of 90 per cent and'then dissolved in boiling water and precipitated by the addition. of sodium chlorid in the 1 5 form of 'its sodium salt. The latter dissolves with a bluevcolor in water and in concentrated sulfuric acid with a violet color.

Example 13.

10 parts of the intermediate product described in the foregoing Examples 1 to 4 are dissolved in 100 parts of concentrated sulfuric acid and a paste prepared from 35 parts of manganese dioxid and 210 parts of concentrated sulfuric acid is introduced at a temperature not surpassing 25 degrees centigrade. The mixture is then stirred for about an hour while maintaining this temperature, poured into water and theyello-wish-brown precipitate formed is filtered off; When dry,

7 it dissolves in sulfuric acid with a reddishbrown color. In dilute acids and alkalies itis insoluble. \Vhen treated With reducing agents, such as bisulfite solution, it assumes a blue color. The reduction product can be retransformed into the yellowish-brown compound by the action of oxidizing means. The

reduction product dissolves in very dilute hot caustic sodasolution with a yellowishgreen color, and with alkaline hydrosulfite solution it produces a greenish-blue vat from which cotton 1s dyed green shades.

.- Example 14. I

. whilst adding some sodium bisulfite, the V blue-solution is then filtered off from the lead sulfate and precipitated with sodium chlorid. The prec pitated product dissolves in dilute acids with a blue color and in alkalies with a green color. of oxidizing agents the blue colored acid solution turns yellowish-brown but the blue color is restored by the addition of reducing agents for example sodium bisulfite. A brilliant greenish blue vat is produced with alkaline hydrosulfite solution.

\Vhat we claim is 1.'In the manufacture of benzanthrone derivatives, converting a benzanthrone com pound into condensation roducts (which are not vat coloring matters by treating the benzanthrone compound with an alkaline condensing agent at a more moderate temperature than that leading to vat-coloring matters.

By the addition 2. In the manufacture of benzanthrone (5 I derivatives, converting a benzanthrone compound into condensation products (which are not vat coloring matters,) by treating the benzanthrone compound with an alkaline condensing agent at a more moderate temperature than that leading to vat coloring matters and separating from vat coloring matter if such be present.

3. rivatives by treating a benzanthrone body witlran alkaline condensing agent at a more moderate temperature than that leading to the substantial formation ,of vat coloring matters, separating from vat coloring matter if such be present and subjecting the condensation product to further condensation.

4. The manufacture of benzanthrone derivative s'by treating a benzanthrone body with an alkaline condensing agent at a more moderate temperature than that leading to the substantial formation of vat coloring matters, separating from vat dyestuff, if any such be present, and treating the product with a strongly oxidizing condensing agent.

As a new article of manufacture a condensation product of benzanthrone which compound is insoluble in alkaline hydrosulfite solution and has a melting point above 300 degrees ccntigrade and dissolves in high boiling organic solvents with a yellow color and in concentrated sulfuric acid With a red color, and which when heated with sulfuric ARTHUR LI'JTTRINGHAUs- HUGO WOLFF. HEINRICH NERESHEIMER.

lhe'manufacture of benzanthrone de-- 

